Evaluation of the ulcerogenic effect of potassium chloride by endoscopy and fecal blood loss.

In a blinded-observer crossover study, 16 volunteers ingested equimolar doses of three different potassium chloride preparations and placebo for nine days in a random order. The irritating effect on the mucosa was evaluated by means of upper gastrointestinal endoscopy and fecal blood loss, measured by reference to the amount of radioactivity in three 24-hour samples after previous injection of 51Cr-tagged autologous red cells. The microencapsulated KCl capsule preparation induced three ulcers, but the total endoscopic group score was not significantly higher than the score with placebo. The total endoscopic group score for the wax-matrix formulation was significantly higher than the score for placebo (P less than .05) and for a new microencapsulated KCl tablet preparation containing a potent disintegrant (P less than .10). We did not find any significant differences in mean fecal blood loss during the four different treatments. A correlation between endoscopic score and fecal blood loss was found in the placebo group (r = .54) and the microencapsulated KCl capsule preparation (r = .56) group.